Fungicidal liquid concentrate with propylene glycol



United States Patent Ofiice 3,3 12,589 Patented Apr. 4, 1967 3,312,589 FUNGICIDAL LIQUID CONCENTRATE WITH PROPYLENE GLYCOL William J. Entley, Charleston, and Harry A. Stansbury,

In, South Charleston, W. Va., assignors to Union Carbide Corporation, a corporation of New York No Drawing. Filed Nov. 26, 1965, Ser. No. 510,101 3 Claims. (Cl. 167-42) This invention relates to a liquid concentrate formulation for fungicidal mixtures.

U.S. Patent 3,166,469 to Pass et al. discloses the advantages of applying fungicidal compositions containing two previously known fungicides in combination, viz. 2-heptadecylglyoxalidine which is sold by Union Carbide Corporation under the common name Glyodin, and n-dodecylguanidine acetate, sold by American Cyanamid Company under the trademark Cyprex and commonly known as Dodine. The terms "Glyodin and Dodine as used hereinafter are intended to refer to the commercially pure chemicals which are the fungicidally active components in formulations containing them.

The utility of this fungicidal mixture has, however, been limited by the solubility characteristics of the two components which are such as to have heretofore precluded development of a stable liquid formulation concentrate. Such a concentrate is convenient to use and thus preferred by orchardists. Glyodin is a waxy solid with a melting point of 62 C. to 68 C. and is thus not readily formulated as a wettable powder. Commercially, it is sold in an isopropanol solution containing 30 percent by weight of Z-heptadecylglyoxalidine in the form of its acetate salt. table powder formulation containing 65 percent by weight of n-dodecylguanidine acetate, the remainder being an inert particulate solid carrier, e.g., bentonite, and about 5 percent of a surfactant.

The two known aqueous formulations for the fungicidal mixture are described in the Pass et al. patent in Examples 1 and 2. One is a liquid mix in which a 30 percent solution of Glyodin in isopropanol and Dodine as a 65 percent wettable powder are charged into a tank full of water and the resulting mixture is continuously agitated tokeep the components in suspension. In the other formulation a dry product is applied as a spray by suspending the dry powder in a large volume of 'water and maintaining vigorous agitation.

The difliculty with these known formulations is that they require handling of a dust material by the applicator which involves mixing problems, contamination of persons and facilities, and waste of some material. In addition, the tank water needs to be continuously agitated to maintain suspension of the dust. I

The present invention provides .a liquid concentrate in which the technical Glyodin and Dodine have been mixed in proportions optimum for fungicidal eifectiveness. The invention utilizes the technically pure active fungicidal ingredients and thus obviates prior formulation of the Glyodin in isopropanol and of the Dodine as a wettable powder as required by the prior art techniques. Being a liquid concentrate, the present formulation is easy to handle and obviates all the problems of working with a dust described above. In addition, the liquid concentrate of this invention forms a solution when added to water so that the actual spray need not be kept under constant agitation.

Essentially, the present invention comprises liquid concentrate formulations containing Glyodin and Dodine characterized by the presence of propylene glycol. It has been found that when certain percentages of propylene Dodine is normally available as a wet' glycol are added to the two-component fungicidal mixture, a stable liquid concentrate formulation is obtained which exhibits excellent sprayability when mixed with water. In this respect the use of propylene glycol has been found critical inasmuch as the use of other common solvents did not result in usable formulations but rather led to formation of turbid suspensions not suited for mixing or spraying. V

The compositions of this invention may contain the two active fungicidal components in a proportion of from about 0.8 part by weight to about 15 parts by weight of Glyodin per part by weight of Dodine. However, in preferred combinations, from 1 to about 8 parts of Glyodin are provided for every part of Dodine and the optimum ratio is about 4 parts of Glyodin for every part of Dodine. Use of this ratio appears to result in most eflfective disease control. The compositions are further characterized in that they contain from about 10 to about 30 parts by weight of propylene glycol per part by Weight of Dodine. It has been found that at least 10 parts by weight of propylene glycol per part of Dodine are required to give readily water-dilutable concentrates. Use of more than 30 parts of propylene glycol results in low toxicant concentration in the concentrate and gives no advantages in stability or sprayability of the diluted concentrate. In addition, the compositions may contain a certain amount of isopropanol or other solvent in which the technical Glyodin material may be commercially available. The liquid concentrate formulations of this invention thus contain from about 10 to about 40 percent by weight of Z-heptadecylglyoxalidine, from about 3 to about 10 percent by weight of n-dodecylguanidine acetate, and from about 50 to about 87 percent by weight of propylene glycol, provided that at least 10 parts by weight of propylene glycol are provided for every part by weight of n-dodecylguanidine acetate.

The liquid concentrates are prepared by'physically admixing the components in the above indicated ratios to result in a clear solution. If the concentrates are used at very low temperatures (ca 0 C.) slight warming may be necessary to maintain a clear, readily dilutable concentrate. If one of the fungicidal components is available in solution, e.g., Glyodin in isopropanol, such a solutionmay be admixed with the other components of the concentrate and the isopropanol optionally evaporated by distillation under reduced pressure.

To demonstrate the criticality of using propylene glycol comparative tests were carried out using the following materials in place of propylene glycol: ethylene glycol, isopropanol, butyl Cellosolve, dimethylformamide, dimethylsulfoxide, Carbitol acetate, Cellosolve acetate, ethylene glycol diacetate, 1,3-butanediol, glycerol.

Use of each of the above materials in the amounts indicated for propylene glycol results in a cloudy, turbid suspension unsuitable for agricultural application.

To determine the effectiveness of the formulation of this invention in agricultural applications, the formulation of this invention was applied to combat bean mildew, bean rust, tomato early blight and cucumber anthracnose in side-by-side tests with the conventional formulations described above, according to the following procedure.

Bean, tomato, and cucumber plants were sprayed on a revolving turntable with the indicated formulation for 30 seconds to apply about milliliters of formulation. The treated plants were then stored at room temperature for a period of 24 hours. After the storage period, one half of the plants were sprayed on the turntable with 200 milliliters of water (indicated as rain treatment) and then dried. The remaining half received no additional treatment. Then all of the test plants were infested with the indicated fungus by brushing their leaves lightly with infested plants from a stock culture, or by spraying them with a stock spore suspension.

The plants were held for visually rated according to 1) =no activity (2)=little control (3) =about 50% effective (4) =excellent control (5 =complete control the following designations:

The results are set forth in Table 1, below. Concentrations of the active toxicants in the applied formulation are given in parts per million for each toxicant.

are provided for every part by weight of n-d0decylguanidine acetate.

2. A fungicidal concentrate as claimed in claim 1 comprising from about 10 to about 40 percent by weight of 2- heptadecylglyoxalidine, about 1 part by weight of n-dodecylguanidine acetate for every 4 parts of 2-heptadecylglyoxalidine, and about 10 parts by weight of propylene gylcol for every part of n-dodecylguanidine acetate.

3. A fungicidal concentrate as claimed in claim 2 comprising from about to about 28 percent by weight of 2- heptadecylglyoxalidine, from about 6 to about 8 percent by weight of n-dodecylguanidine acetate, and about 65 percent by weight of propylene glycol.

TABLE I.-FUNGICIDAL TEST RESULTS FOR COMBINATIONS OF GLYODIN AND DODINE IN DIFFERENT FORMULATIONS Ratings Counts 1 Concentration of active Formulation toxicant in Early Blight Bean Rust water (p.p.m.) Cucumber, Anthrac- No Rain nose, Rain 3 No Rain Rain 2 N 0 Rain Rain 2 Dodine (tehnical) 3 250 3 3 4 3 4 5 5 5 9 23 60 4 4 3 3 4 4 4 4 39 89 15 2 2 2 2 3 3 1 3 56 84 Dodine (65% wettable powder) 250 2 2 3 3 4 4 5 4 91 28 60 2 3 4 4 4 4 4 4 63 49 15 3 3 2 2 3 3 3 3 78 Dead G1 odin" 30 solution in iso ro anol 1,035 2 2 2 2 5 5 5 5 70 23 y p p 259 2 2 2 2 4 4 5 5 44 57 65 1 1 1 1 1 1 4 4 64 42 Glyodin (307 solution in isopropanol) plus Dodine (technicalyfli 1, 035-1 250 5 5 5 5 31 259+60 3 3 3 3 5 5 5 5 22 56 65-1-15 3 3 3 3 5 4 3 32 36 Glyodin (307 solution in isopropanol) plus Dodine (65% wettable powder) 1, 035+250 5 5 5 26 259+60 4 4 4 4 5 5 4 5 53 65+15 4 4 3 3 5 4 5 3 66 65 Glyodin (technical) plus Dodine (technical) in propylene glycol 1, 035+250 5 5 5 5 34 36 259+60 4 4 4 4 5 5 4 5 39 59 65-1-15 3 3 4 4 3 4 5 4 48 43 Control 1 l 1 l 1 1 1 1 136 169 1 Number of lesions per 4 leaves. 2 Water (200 m1.) sprayed on plants 24 hours after treatment. 3 Dissolved in ethyl alcohol before addition of water. The final fo 4 The sprayed plants showed a phytotoxic response.

rmulations at 250 ppm. contained 10 percent alcohol by volume.

5 The concentrate contained 65 percent by weight of propylene glycol in each instance;

It can be seen that the liquid formulation of this invention possesses the advantages of a liquid formulation with undiminished fungicidal efiectiveness.

What is claimed is:

1. A fungicidal liquid concentrate formulation comprising from about 10 to about 40 percent by weight of 2- heptadecylglyoxalidine, from about 3 to about 10 percent References Cited by the Examiner UNIT ED STATES PATENTS 1/1965 Pass 167-22 References Cited by the Applicant UNITED STATES PATENTS 3,166,469 1/1965 Pass et al. SAM ROSEN, Primary Examiner. S. I. FRIEDMAN, Assistant Examiner. 

1. A FUNGICIDAL LIQUID CONCENTRATE FORMULATION COMPRISING FROM ABOUT 10 TO ABOUT 40 PERCENT BY WEIGHT OF 2HEPTADECYLGLYOXALIDINE, FROM ABOUT 3 ABOUT 10 PERCENT BY WEIGHT OF N-DODECYLGUANIDINE ACETTE, AND FROM ABOUT 50 TO ABOUT 87 PERCENT BY WEIGHT OF PROPYLENE GLYCOL, PROVIDED THAT LEAST 10 PARTS BY WEIGHT OF PROPYLENE GLYCOL, ARE PROVIDED FOR EVERY PART BY WEIGHT OF N-DODECYLGUANIDINE ACETATE. 